Atomic Flame Research Articles

Evaluating the Effects of Heavy Metals on Seminal Fluid Anti Oxidants Status and Semen Parameters among Males with Infertility at Tertiary Health Centre in Nigeria

Abstract Introduction: There are evidences of a reduction in male fertility potential globally. This, coupled with the limitation of the gold standard investigative tool of male infertility, has become necessary that focus should be on elucidating the aetiopathogenic causes of male fertility. This includes the impact of environmental toxic products such as levels of heavy metals that have been proposed to impact both the sperm quality and seminal antioxidant status. The study assessed how the seminal concentrations of specific heavy metals such as cadmium, lead and Iron affect the seminal fluid analysis (SFA) parameters and seminal antioxidant status of males exhibiting abnormal parameters of sperm, analysing infertile male patients consecutively in a cross-sectional manner, with at least one abnormal SFA parameter, at a tertiary health centre. Materials and Methods: One hundred and thirty consenting males who have one or several anomalies with sperm characteristics were selected as subjects. Semen samples were collected, processed and centrifuged. The supernatants were analysed for the heavy metals using Buck Scientific 210/211VGP Flame Atomic Absorption Spectrophotometers 220GF Graphite Furnace and 220AS Autosampler and seminal Vitamins C and E, using spectrophotometric method and glutathione peroxidase, whereas catalase was analysed using ELISA method. Results: Subjects’ seminal levels of Cd, Fe and Pb were notably greater than those of controls, respectively. In addition, individuals’ levels of seminal antioxidants were noticeably lower than controls. Seminal antioxidant status and Seminal Cd, Fe and Pb were positive and negative significantly correlated with sperm count and active motility, respectively. Conclusion: Laboratory quantification of the seminal concentrations of these heavy metals in the evaluation of males with infertility, especially those still regarded as idiopathic, because of limitations of investigative tools and biomarkers, will be of clinical utility, in both the management and prevention of sperm quality deterioration.

Health Risk of Heavy Metal and Genotoxicity of Polycyclic Aromatic Hydrocarbons (PAHs) in Extra-Virgin Olive Oils (EVOO) Available in PortHarcourt Metropolis, Nigeria

This research aims at determining the loading of contamination of some popular brands of extra-virgin olive oil (EVOO) in Port Harcourt, Nigeria, with genotoxic PAHs and Heavy Metals to ascertain its safety for consumption. The health risk associated with these heavy metals will be calculated and assessed. Extra virgin olive oil has experienced a surge in its consumption all around the world owing to its high nutritional content. Contamination with genotoxic PAHs and Heavy Metals can cause severe health defects if consumed regularly. PAHs and heavy metals are two distinct groups of ubiquitous contaminants with grave health consequences such as Tumorigenesis, carcinogenesis, organ failures etc. Samples of EVOO were analysed with Gas Chromatography/Mass Spectrophotometer and Flame Atomic Absorption Spectrophotometer (FAAS) for PAHs and heavy metals respectively. After extraction with Dichloromethane and digestion with aqua regia (HCl/HNO3; 3:1) respectively, the results showed the presence of few genotoxic PAHs such as benzo[a]pyrene, PAH4 and PAH8 with concentrations above regulatory limits of 0.002µg/g, 0.01µg/g and 0.01µg/g respectively. Among the heavy metals, Pb and Cd showed the most alarming levels of contamination of the heavy metals, above regulatory limits of 0.1µg/g and 0.05µg/g, however, analysis with Health Risk Index of consumption showed all samples were safe for consumption.

Analysis and Detection of Heavy Metals Content in Some Selected Packaged Fruit Juices of Kathmandu City by Flame Atomic Absorption Spectroscopy

The determination of level of heavy metals in packaged fruit juices is crucial, as extended exposure to even small quantities of these toxic element can cause severe health issues and chronic poisoning. Hence, it is essential to gather comprehensive data on the presence of heavy metals in packaged fruit juice samples. The objective of this research work is to determine heavy metals (Fe, Cu, Zn and Pb) in four different types of packaged fruit juice samples viz Apple, Mango, Orange and Lychee of four different popular brands bought from retail market of Kathmandu city by flame atomic absorption spectroscopy and compare with acceptable limit set by WHO/FAO. Wet acid digestion method was used for digestion process of packaged fruit juice samples. The concentration of Iron were ranged from 0.572-0.762mg/L in Orange juices; 0.362-0.624mg/L in Mango juices; 0.277-3.649mg/L in Apple juices; 0.279-1.770mg/L in Lychee juices respectively. Copper concentration were ranged from not detected (ND)-0.574mg/L in Orange juices; ND for all selected samples in Mango juices; ND- 0.023mg/L in Apple juices; ND-0.041mg/L in Lyclee juices. Similarly Zinc concentration were ranged from 0.0511-0.2026mg/L in Orange juices; ND-0.0700mg/L in Mango juices; ND for all selected samples in Apple juices; ND-0.0287mg/L in Lychee juices. The concentration of hazardous element Lead was found below detection limit in all selected packaged fruit juice samples. The heavy metals concentration in selected brand of packaged fruit juice samples was in following order: Fe>Zn>Cu> Pb. Int. J. Appl. Sci. Biotechnol. Vol 12(3): 158-165.

Application of KH-RT model in lifting flame of methanol jet atomization

Abstract For the methanol jet atomization in a co-flow gas lifting flame, the self-developed WAVE model and KH-RT model were employed using the Saturne program to simulate the primary breakup of the jet column and the atomization of spray particles. Additionally, the unsteady flamelet model was utilized to simulate the combustion process. Comparing the calculated flame lifting height, droplet diameter distribution, and velocity distribution with experimental results demonstrates the atomization model’s ability to accurately capture the methanol fuel atomization process. This comparison verifies the reliability of both the atomization and combustion models, indicating their high accuracy. The study shows that upon injection from the nozzle, methanol fuel rapidly diffused, creating a cone-shaped spray structure. The high concentration of OH radicals is located close to the boundary between the regions of OH radical distribution and methanol distribution, gradually spreading downstream of the methanol jet. Furthermore, an increase in fuel flow rate resulted in a reduction in the flame’s lift height.

Oznaczanie antymonu i jego związków w powietrzu na stanowiskach pracy

Antimony is used as an additive in font and bearing alloys along with other metals. Antimony in metallic form is not classified as a health hazard, while its salts have been so classified. Some antimony compounds have been classified as carcinogens. The applicable value of the maximum allowable concentration (MAC) in air at workplaces is 0.5 mg/m3 (MRPiPS ordinance, 2018). The purpose of this study was to develop a method for the determination of antimony for occupational exposure assessment in the range of 1/10–2 of the proposed MAC values. The method consists of collecting antimony and its airborne compounds from an MCE filter, mineralizing the filter in aqua regia at 150°C, then determining the antimony content in the sample using atomic absorption spectrometry (AAS) with flame atomization. The method for the determination of antimony is presented in the form of an analytical procedure, which is included in the appendix. The scope of the article includes health and environmental health and safety issues that are the subject of research in health sciences and environmental engineering

Exploring electric field forces and polarization influence on combustion in Fe-additive fuel droplets

The application of electrical techniques such as electric field, polarization, and ionization in the field of combustion makes many positive developments possible. The electric field effect offers significant advantages in controlling flame stability and reducing soot formation during the combustion of fuels. Also, the conditioning effect can improve particle oxidation during combustion for hydrocarbon fuels containing metal particle inclusions with high calorific value. This study focuses on investigating the combustion and atomization behavior of Fe additive diesel fuel droplets at electric field strengths of E = 5 V/m, E = 6.7 V/m, and E = 10 V/m and in positive (↑) and negative (↓) electric field directions. The experiments were carried out by igniting a fuel droplet suspended on a ceramic wire with an arc at the center of the electric field between two conductive plates in a combustion chamber with optical apertures. The combustion processes were recorded with an optical system consisting of a high-speed camera and a thermal camera. Combustion and atomization behavior were characterized by sequential flame and droplet atomization images, respectively. The droplet shape change and flame behavior results were comparatively evaluated according to the d2-law. Ignition delay and extinction times were determined by processing threshold technique and maximum flame temperatures were determined by processing thermal camera images. The results showed that increasing the electric field intensity in the negative electric field direction resulted in improved soot oxidation, and Fe particles burnt efficiently. Ignition delay times showed a decreasing trend with an electric field effect and an increasing trend with the addition of Fe particles. The highest maximum flame temperature and lowest extinction time were recorded as 785 K and ∼ 578.34 ms for Diesel/Fe/100(↓) fuel droplet, respectively and Fe particles did not exhibit microexplosion phenomena at E = 10 V/m. In this study, it has been shown that an effective oxidation can be achieved for Fe particles by increasing the mobility of ionized species in the flame zone under the effect of electric field and a homogeneous thermal field can be created in the flame zone even in fuels with particle addition at increasing electric field intensities.

A MWCNTs@CuAl2O4@SiO2 Nanocomposite for the Speciation of Cr(III), Cr(VI), and Total Chromium Prior to High-Resolution Continuum Source Flame Atomic Absorption Spectrometric Determination

A solid-phase microextraction (SPME) method had been applied to speciate chromium in natural and wastewater samples. MWCNTs@CuAl2O4@SiO2 nanocomposite was synthesized by sol–gel and calcination methods and then characterized using SEM, FTIR, and XRD techniques. MWCNTs@CuAl2O4@SiO2 was used to extract Cr(VI) as pyrrolidine dithiocarbamate chelates. Some analytical parameters involving pH, ligand (APDC) and adsorbent amounts, sample initial and final volume, and the effects of matrices were tested and optimized. For the oxidation of Cr(III) to Cr(VI), potassium permanganate was used, and after that, the presented method was applied to determine the total chromium levels. The calculations were carried out to obtain Cr(III) concentration by finding differences between total chromium and Cr(VI) concentrations. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 6.2 µg L−1 and 20.8 µg L−1, respectively. The proposed method was successfully applied for chromium speciation in wastewater samples.

Characterization, Efffects and Chemical Treatment of Heavy Metals in Produced Water from Injection Wells using Hydroxide Precipitation

Produced water obtained from five (5) water injection Wells in the Niger Delta area Nigeria were analysed for heavy metal ion concentrations using Themo Elemental Flame Atomic Absorption Spectrophotometer (AAS). Results obtained show that concentrations of lead (Pb2+), cadmium (Cd2+), chromium (Cr2+), nickel (Ni2+), cobalt (Co2+), vanadium (V2+), zinc (ZN2+), mercury (Hg+), silver (Ag+) and copper (Cu2) were above acceptable limits as specified by Environmental Guidelines and Standard for Petroleum Industries in Nigeria (EGASPIN). The concentrations of As2+, Fe2+, K+ and Mn2+ were within specification. Commingled produced water from the five water injection Wells were subjected to hydroxide precipitation using Ca(OH)2 at concentrations of 10, 20, 30, 40 and 50 ppm respectively. Results obtained show that all the heavy metal ions reduced within acceptable limit at 30 ppm chemical concentration. Heavy metal ions reduced with increase in chemical concentration with a corresponding increase in the pH of the solution which was however still within specification. The hydroxide converts the metal ions dissolved in solution into solid particles for easy sedimentation. Ca(OH)2 precipitates metal ions by changing the pH and electro-oxidizing potential of the solution. Properly treated produced water can be reinjected into the reservoir to enhance oil recovery, used in agriculture for irrigation purposes, discharged into the sea and other water bodies during offshore operations or even used in drilling services. Produced water discharged into the soil are non-biodegradable so must be adequately treated before discharge. Plants pick up heavy metals through their roots by the release of a variety of root exudates which changes the rhizosphere pH of the metal ion in solution thereby making them bioavailable for plant uptake by osmosis. Heavy metals in plants can exert a variety of toxic actions by damaging plant chloroplast thereby disturbing photosynthesis. Humans take in heavy metals into their system by consuming contaminated plants, water as well as inhaling contaminated air. Consumption, ingestion and inhalation of heavy metals by humans can cause a wide range of ailments such as cardiovascular diseases, kidney related problems, neurocognitive diseases, renal damage, heart disease, coronary artery disease, lung fibrosis, nasal cancer.

The effect of deicing reagents on soil properties of the roadside lawns in Novosibirsk

The aim of the study was to evaluate the effect of deicing reagents on soil properties of the roadside lawns in Novosibirsk. Location and time of the study. Roadside lawns and a public green square in the central part of the Novosibirsk city. Field and laboratory work was performed in late 2023–early 2024. Methods. Soil samples were analyzed according to the following methods: preparation of aqueous extract was done at the ratio of soil:solution of 1:5; determination of specific electrical conductivity and water pH was performed using the electrodes HI763123 and ESC-10603, respectively; the content of water-soluble sulfates was measured with precipitation of sulfate ions by barium chloride and determination of barium sulfate by turbidimetric method; water-soluble sodium was measured by atomic absorption spectrometer with flame atomization Kvant-2A; water-soluble chlorides were measured by ion-selective electrode Econix ECOM-Cl; and water-soluble phosphates were measured by molybdenum-blue spectrophotometric method. The statistical processing of the data was carried out using the principal components analyzis, as well as by variation, regression, correlation and variance analyses. Results. Application of deicing reagents (DR) altered most significantly the content of water-soluble sodium and chlorine in the urban soils of roadside lawns, the values of which reached as high as 443 mg Na/kg and 511 mg Cl/kg. Sulfate and phosphate concentrations depended on the DR application to a much lesser extent. The relationship of chlorine content with the sodium one was described by a simple linear regression equation with a coefficient of determination (R2) equal to 0,92: Cl = 1,503 × Na – 34,655, where Cl and Na concentrations are presented in mg/kg. A close positive relationship (R2 = 0,87) was also found between the sum of all four analyzed ions (SI) and specific electrical conductivity (EC), described by the linear equation SI = 0,0078 × EC – 0,985, where SI (sum of Na+, Cl–, SO42–, and PO42– ions) is represented in cmol(eq)/kg, and EC in μS/cm. Conclusions. In the urban soils of roadside lawns, as compared to the central part of the public square, a significant increase in the content of water-soluble sodium and chlorine was found: 7–24 times and 30–80 times, respectively. The increase in the concentration of these elements was associated with a 3,3-fold increase in the value of specific electrical conductivity (which characterizes the general level of soil salinization with easily soluble salts) and a change in the reaction from "slightly alkaline" to "moderately alkaline". Such significant changes in the chemical properties of the urban roadside soils are caused by the DR use, which may result in the suppression of growth and development of plants, especially tree species less adapted to salt pollution, eventually leading to their dying-off.

Bioaccumulation Capacity of Onion (Allium cepa L.) Tested with Heavy Metals in Biofortification.

On a worldwide scale, A. cepa is among the most commonly consumed vegetables. In Europe, the leading onion producers are Russia, the Netherlands, Spain, Poland and Germany. In this study, the bioaccumulation of heavy metals (Cr, Cu, Zn, Ni, Fe, Mn, Co, Sr, Cd and Pb) by Allium cepa L. plants was followed under hydroponic conditions. The heavy metals were applied at six concentrations (0, 25, 50, 100, 200 and 400 mg L-1) over three weeks. The quantitative analysis of selected heavy metals in plant tissues (bulbs, roots and assimilation leaves) was performed using atomic absorption spectrometry with flame atomization (F-AAS). The accumulation of metal ions was strongly dependent on their concentrations in the solution and the analyzed parts of plants. The highest accumulation of metal ions was confirmed for the roots and ranged from 8.48 to 5912.34 µg g-1 DW (dry weight). All parts of A. cepa were characterized by the high accumulation of Mn2+. The lowest accumulation was confirmed for Co2+ in the roots, Pb2+ in the assimilation leaves and Cu2+ in the bulbs of onion. Moreover, the study showed that the highest concentrations of heavy metals decreased the growth of bulbs and even caused them to die off. In contrast, lower concentrations of some elements stimulated plant development.

Assessment of the Radiation Situation and the Presence of Heavy Metals in the Soil in the Poleski National Park

The aim of the research in the Poleski National Park was to determine the concentration of radionuclides and heavy metals in the soil and to evaluate the absorbed dose and the average annual effective dose as a result of external exposure to ground-based radiation sources. The spread of anthropogenic radionuclide concentration in the Poleski National Park was the highest. This is a first-of-its-kind study in Poland. The annual effective dose calculated for the Poleski National Park was over three times higher than the average worldwide value. Soil samples were subjected to mineralization using a TITAN MPS with a rotor. Subsequently, the metals in the obtained solutions were determined using the atomic absorption spectrometry method with flame atomization (AAS FM). The content of copper Cu, nickel Ni, lead Pb, cadmium Cd, and chromium Cr did exceed the average content neither in Europe nor around the world. The soils of the Poleski National Park are characterized by pollution with the tested heavy metals, especially cadmium Cd.

Detection of Lead (Pb) and Cadmium (Cd) Concentrations and Hazards in Some Baby Food Samples

This study was conducted to detect the concentration of lead and cadmium in baby foods, (18) samples were examined, which are the most available from various local markets in the city of Baghdad (at a rate of (9) samples of baby food consisting of cereals and (9) samples of baby foods consisting of vegetables). All samples were examined using an atomic flame absorptiometry (AAS-7000), all results showed the presence of lead and cadmium and the highest concentration value of lead in baby foods consisting of cereals (1.0986) and cadmium in baby foods consisting of vegetables (0.0015) ppm. Lead exceeded 100% limitations and cadmium did not exceed that. The results reported on the risks of contamination, as the mean daily intake (g/kg/d) for lead (1.3538) and cadmium amounted to (0.010), and the target hazard quotient index was high for the index (THQ>10) for lead in most of the samples examined and reached (THQ<10) in some samples examined, while cadmium all samples reached an index of (THQ<10). The study showed an increase in lead concentrations and perceptible risks and did not report an increase in cadmium concentrations outside the determinants, but it warns of imperceptible risks to the consumer. The study showed statistically significant differences between the levels of lead and cadmium and between the studied species and did not show statistically significant differences between the origins at the level of significance (0.05). It has been shown that these products pose a risk to children when consumed, so these products must be banned and ways must be found to reduce or prevent these pollutants with these products or find appropriate alternatives.

Influence of the gene pool of the breed on the content and variability of copper in the liver of pigs

The average level and variability of copper in the liver of pigs of different breeds were studied. Samples of parenchymal organs from pigs were taken immediately after slaughter and analysed at the analytical centre for collective use of V.S. Sobolev Institute of Geology and Mineralogy of the Siberian Branch of the Russian Academy of Sciences using the method of atomic absorption spectrometry with flame and electrothermal atomisation on the SOLAAR M6 spectrometer (USA) by GOST 26929-94 Raw materials and food products— sample preparation Mineralization to determine the content of toxic elements. A normal distribution of the trait was found only in the Landrace breed (W = 0.94). In pig breeding areas, the content of heavy metals in soil, water and feed was studied, which did not exceed the maximum permissible concentration. The most significant variability of the microelement was observed in the Kemerovo breed, the least - in the Landrace breed. The full copper content was marked in the early ripening meat breed and the minimum in the Landrace breed. A smaller interquartile range about the Kemerovo and early meat breeds characterised the level of copper in the liver of Landrace pigs.

Simultaneous Measurement of Trace Levels of Hg, As, Sb, and Bi in Coastal Seawater with a Multichannel Chemical Vapor Generation Atomic Fluorescence Spectrometer.

Trace levels of Hg, As, Sb, and Bi in coastal seawater have been simultaneously detected by a laboratory-built multichannel chemical vapor generation coupled to an atomic fluorescence spectrometer. The system was configured with a built-in electrochemical H2 generator as the fuel supplier to replace chemical H2 produced by the oxidation of potassium borohydride under acidic conditions in traditional instruments. The electrochemical H2 generator not only isolated the atomization process from the chemical vapor injection process but also improved the stability of atomization, excitation, and fluorescence emission in the hydrogen flame, making it easier to optimize conditions for CVG while introducing evaporating multielement vapors. Calibrations were obtained using a mixed standard solution of Hg(II), As(III), Sb(III), and Bi(III). The addition of KBr to a 3% (v/v) HCl solution was selected as the preservative to ensure the stability of 0.10 μg/L Hg(II) in a multielement standard solution for at least 15 days while also preserving μg/L levels of As(III), Sb(III), and Bi(III) stable. The method detection limits (LOD, 3σ) were 0.001, 0.015, 0.010, and 0.005 μg/L for Hg, As, Sb, and Bi, respectively. The relative standard deviations (RSD, n = 7) of the standard spiked seawater samples were 3.2% (0.020 μg/L Hg), 1.2% (0.50 μg/L As), 1.0% (0.50 μg/L Sb), and 3.5% (0.050 μg/L Bi), respectively. The recoveries of seawater samples spiked with different salinities were in the range of 84.5%(Sb)-114%(Hg). The system has been successfully applied to the simultaneous analysis of the four elements in the seawater samples collected from Xiamen Bay, Southeast China.

Toxic element determination in selected cosmetic products: health risk assessment.

The aim of this research was to determine the content of arsenic (As), cadmium (Cd), lead (Pb), and nickel (Ni) in selected lipsticks and face foundations of different price categories and the health risk assessment associated with these toxic elements via dermal and oral exposure. The samples (10 lipstick and 10 face foundations) were purchased from local markets in Belgrade, Serbia. The samples were prepared by acid digestion and analyzed by atomic absorption spectrometry (flame atomization for Cd, Pb, and Ni and electrothermal atomization for As). Arsenic was found in 50% of lipstick samples and in only two face foundation samples with the highest concentration of 0.28 mg/kg in the lipstick sample. Lead concentration was in the range of 1.15 to 5.12 mg/kg in ten samples. Nickel was found in five samples out of 20, with the highest concentration of 4.20 mg/kg. Cadmium was found in only one face foundation sample in the cheaper price range (1.11 mg/kg). The obtained results indicate that concentrations of As, Pb, Cd, and Ni were within the permissible limits according to Serbian legislation. Health risk associated with these elements was assessed as non-carcinogenic and carcinogenic risk. Obtained hazard quotients (HQs) and hazard indexes (HIs) were below 1, indicating the absence of significant non-carcinogenic health risk due to exposure to these toxic elements (TEs). The carcinogenic risk results show that investigated cosmetic products can be considered low-risky due to the possibility of causing malignant disease.

UV-C Seed Surface Sterilization and Fe, Zn, Mg, Cr Biofortification of Wheat Sprouts as an Effective Strategy of Bioelement Supplementation.

Metalloenzymes play an important role in the regulation of many biological functions. An effective way to prevent deficiencies of essential minerals in human diets is the biofortification of plant materials. The process of enriching crop sprouts under hydroponic conditions is the easiest and cheapest to conduct and control. In this study, the sprouts of the wheat (Triticum aestivum L.) varieties Arkadia and Tonacja underwent biofortification with Fe, Zn, Mg, and Cr solutions in hydroponic media at four concentrations (0, 50, 100, and 200 µg g-1) over four and seven days. Moreover, this study is the first to combine sprout biofortification with UV-C (λ = 254 nm) radiation treatment for seed surface sterilization. The results showed that UV-C radiation was effective in suppressing seed germination contamination by microorganisms. The seed germination energy was slightly affected by UV-C radiation but remained at a high level (79-95%). The influence of this non-chemical sterilization process on seeds was tested in an innovative manner using a scanning electron microscope (SEM) and EXAKT thin-section cutting. The applied sterilization process reduced neither the growth and development of sprouts nor nutrient bioassimilation. In general, wheat sprouts easily accumulate Fe, Zn, Mg, and Cr during the applied growth period. A very strong correlation between the ion concentration in the media and microelement assimilation in the plant tissues (R2 > 0.9) was detected. The results of the quantitative ion assays performed with atomic absorption spectrometry (AAS) using the flame atomization method were correlated with the morphological evaluation of sprouts in order to determine the optimum concentration of individual elements in the hydroponic solution. The best conditions were indicated for 7-day cultivation in 100 µg g-1 of solutions with Fe (218% and 322% better nutrient accumulation in comparison to the control condition) and Zn (19 and 29 times richer in zinc concentration compared to the sprouts without supplementation). The maximum plant product biofortification with magnesium did not exceed 40% in intensity compared to the control sample. The best-developed sprouts were grown in the solution with 50 µg g-1 of Cr. In contrast, the concentration of 200 µg g-1 was clearly toxic to the wheat sprouts.

A Simple Approach for Fe Determination in Beer by using Dispersive Liquid-Liquid Microextraction and Flame Atomic Absorption Spectrometry

In this work, a new method for Fe extraction and preconcentration from beer by using dispersive liquid-liquid microextraction (DLLME) and determination by flame atomic absorption spectrometry (F AAS) was developed. Although in DLLME the use of an extraction solvent is mandatory (at least in theory), which is combined with a disperser solvent, in this work only the extraction solvent was used. For Fe extraction by DLLME, the type and volume of extraction solvent, sample volume, type of complexing agent, sample pH, salting out effect, and the number of washing cycles after extraction were evaluated. Thus, after optimization, 10 mL of beer, 75 µL of 1,2-dichlorobenzene of extraction solvent, 500 µL of 0.5% (w/v) pyrrolidine ammonium dithiocarbamate (APDC) as complexing agent were used. It is important to mention that pH adjustment, salt addition or washing cycles were no required. For Fe determination after DLLME, an external calibration curve was performed (R2 > 0.99) by direct extracts (reference solutions through DLLME) introduction in the conventional nebulization system of F AAS instrument. The accuracy evaluation was performed by results comparison with those obtained after microwave-assisted digestion (MAD) and Fe determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The Fe concentration in the studied samples ranged from 59.7 to 68.2 µg L-1 and the limit of quantification for DLLME/F AAS method was 9.0 µg L-1. Finally, the proposed method DLLME/F AAS was applied for Fe determination in several beer samples showing simplicity, low operational costs, suitable accuracy (104 to 119%) and precision (better than 13%), opening the possibility for its use in routine analysis for Fe determination in beer.

Study of the Adsorption Efficacy of Cr(III) on a Metal Oxide-Based Material Derived from the Quartz Sand Enrichment Process

In the present study, the efficacy of chromium removal from water media was studied. For this purpose, a metal oxide based material, derived from the enrichment process of quartz coastal sand was used as possible adsorbent of chromium (III) ions. Following additional modification of the adsorbent, the effect of operational parameters including pH, contact time and Cr(III) concentration were studied according to one-factor-at-a-time procedure. Adsorption efficacy was assessed by the measurement of the remaining chromium concentration in solution, after adsorption. Atomic absorption spectroscopy technique, with flame atomization was used for the determination of chromium concentration in solution. Obtained results revealed that selected material exhibited higher adsorption efficacy in alkaline solution (pH = 6-9). The maximum removal efficacy (>93%) was achieved after 180 minutes of contact time, with an adsorbent dosage of 5 g/L and initial chromium concentration 20 mg/L. The adsorption process for Cr(III) follow the Freundlich isotherm and gives high correlation coefficient R². Calculations performed based on the Langmuir isotherm showed that the maximum adsorption efficiency of Cr³⁺ in the natural metal-oxide material has resulted 10 mg/g or 10000 μg/g. Pseudo second order reaction kinetics has provided a realistic description for removal of Cr(III) from solution with high correlation coefficient R² of (0.999). The adsorption isotherms were better described by the Freundlich equation (R² = 0.934). Adsorption of trivalent chromium ions onto selected material followed the pseudo second order model (R² = 0.996). Hence, the residual materials derived from the enrichment processes of quartz sand can be used as alternative adsorbent for the removal of trivalent chromium ions from aqueous solutions.

A Simple and Effective Quantification of Water‐Soluble Rhodium in Soil Samples by Magnetic‐Colloidal‐Gel‐Assisted Dispersive Solid Phase Extraction

AbstractIn this study, a simple, sensitive and environmentally friendly method was developed for the determination of water‐soluble rhodium in soil samples. For this purpose, rhodium was preconcentrated/separated by a dispersive solid phase extraction method (dSPE) and determined by an atomic absorption spectrophotometer with flame atomizer, equipped with a slotted quartz tube (SQT‐FAAS). In the dSPE method, a magnetic colloidal gel (magnetic nanofluid) was produced by mixing Fe3O4 based magnetic nanoparticles (MNP), and deep eutectic solvent (DES) obtained from the mixture of choline chloride and phenol (1 : 3). The optimized system showed good linearity in the concentration range of 17–447 μg/kg. While recording a detection limit (LOD) of 4.26 μg/kg, an over 200‐fold improvement in the detection power was obtained based on the comparison of LODs of the developed method and FAAS. Applicability and accuracy of the developed method were validated by spike recovery results that fell in the range of 89–106 %, using the matrix matching method to boost quantification accuracy in the soil samples.

Determination of Rhodium in Soil by Dispersive Solid-Phase Extraction (DSPE) with Manganese Ferrite Nanoparticles and Flame Atomic Absorption Spectrometry (FAAS)

Manganese ferrite (MnFe2O4) nanoparticles-assisted dispersive solid-phase extraction (MF-DSPE) was developed for the determination of rhodium (Rh) in soil samples at low levels with good accuracy and precision by flame atomic absorption spectrometry (FAAS). The synthesis of MnFe2O4 nanoparticles was carried out in a microwave system by a rapid procedure. The pH, buffer volume, sorbent mass, sample volume, eluent volume/concentration, and mixing time were identified with univariate optimization. Under the optimal conditions, the limits of detection (LOD) and quantitation (LOQ) were 4.4 and 14.7 µg L−1, respectively. The sensitivity was improved by 121.9-fold based upon comparison of the limits of detection with and without preconcentration. The applicability was investigated by spiking rhodium into soil extracts, and good recovery results between 91.2% and 122.2% were achieved using matrix matching calibration. The results showed that MF-DSPE-FAAS determines low levels of rhodium in soil with good accuracy and precision.